Fraction and fraction test
Rests and tuplet tests
Add some methods to Fraction and Song classes
Change structure of chords, notes and tuplets
Merge branch 'implement_ADT' of github.com:Jdhaimson/abcmusicplayer into implement_ADT
Merge branch 'implement_ADT' of github.com:Jdhaimson/abcmusicplayer into FixingLexerParserBugs
updated MusicPlayerHeader, added parse method